BMI Calculator
Calculate your body mass index from height and weight in metric or US units, see your WHO weight category and the healthy weight range for your height.
For general information only — not medical advice. Results are estimates; talk to a doctor or qualified health professional about your own health.
How to use
- 1Choose metric or US units and enter your height and weight.
- 2Read your BMI, its category and the weight range considered healthy for your height.
How it's calculated
BMI = weight (kg) ÷ height (m)². Adult categories (WHO): under 18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, 30 and over obesity.
Frequently asked questions
Is BMI accurate for everyone?
No. It doesn't distinguish muscle from fat, so muscular people can score as overweight. It's a screening tool, not a diagnosis.
Are the ranges different for Asian adults?
Yes. WHO suggests lower action points for many Asian populations — around 23 for increased risk and 27.5 for high risk.
Can I use this for children?
No. Children and teens need BMI-for-age percentiles, which account for growth. Use a pediatric BMI calculator.